Deactivation of Uropathogenic Proteus Bacterial Toxin by Polyphenols of Tamarindus indica Bark: A Robust Inhibition of Hemolysis

摘要

Increasing evidence of multi-antibiotic resistance in bacterial pathogens necessitates medicinal plants as an alternate therapy of infection control and management. Tamarindus indica L. is widely investigated but limited information is available on its bark (Ti -b). Ethanol extract of twelve medicinal plants including Ti -b were investigated for their activities to inhibit hemolysis caused by multi-drug resistant uropathogen, Proteus . Proteus vulgaris among other Proteus species was found as highly hemolytic. Hemolysis caused by cell free hemolysins of P. vulgaris was predominant (75%) over that of cell-associated and intracellular hemolysins. This toxin mediated hemolysis of human erythrocyte cells was potentially inhibited by Ti -b extract although its antimicrobial activity was too low. Bioactive inhibitor in Ti -b extract was detected as polyphenol, which enabled to deactivate the active site of hemolysins and thereby protected blood cells from toxin mediated hemolysis.